Now that the upstream Type-C PHY code is getting broader test coverage we
got reports of USB devices plugged in during boot or those plugged in for
the first time after boot occasionally not working correctly.
This is partially caused by the USB2 parts of the PHY being left in an
unknown state by the previous boot stages. We reset all other parts during
probe but forgot about the USB2 PHY so let's fix that and actually reset
and power off the USB2 PHY as well.

Reported-by: James Calligeros <jcalligeros99@gmail.com>
Reported-by: Janne Grunau <j@jannau.net>
Fixes: 8e98ca1e74db ("phy: apple: Add Apple Type-C PHY")
Signed-off-by: Sven Peter <sven@kernel.org>
---
 drivers/phy/apple/atc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/phy/apple/atc.c b/drivers/phy/apple/atc.c
index c8a58ee64b7aad3205df51cf16ae778471ad2c5d..ab0b40b72533f1b3878b646b59820c730239e85c 100644
--- a/drivers/phy/apple/atc.c
+++ b/drivers/phy/apple/atc.c
@@ -2227,6 +2227,7 @@ static int atcphy_probe_finalize(struct apple_atcphy *atcphy)
 	_atcphy_dwc3_reset_assert(atcphy);
 
 	/* Reset atcphy to clear any state potentially left by the bootloader */
+	atcphy_usb2_power_off(atcphy);
 	atcphy_power_off(atcphy);
 	atcphy_setup_pipehandler(atcphy);
 

---
base-commit: add66a6673bc4aacd0ef0f3c4a51271501770b17
change-id: 20260107-atcphy-coldboot-fix-08652d404347

Best regards,
-- 
Sven Peter <sven@kernel.org>

On Thu, 08 Jan 2026 20:12:06 +0100, Sven Peter wrote:
> Now that the upstream Type-C PHY code is getting broader test coverage we
> got reports of USB devices plugged in during boot or those plugged in for
> the first time after boot occasionally not working correctly.
> This is partially caused by the USB2 parts of the PHY being left in an
> unknown state by the previous boot stages. We reset all other parts during
> probe but forgot about the USB2 PHY so let's fix that and actually reset
> and power off the USB2 PHY as well.
> 
> [...]

Applied, thanks!

[1/1] phy: apple: atc: Reset USB2 PHY during probe as well
      commit: bc148def8924e43245c353c52ced47079a5026da

Best regards,
-- 
~Vinod

On Thu, Jan 08, 2026 at 08:12:06PM +0100, Sven Peter wrote:
> Now that the upstream Type-C PHY code is getting broader test coverage we
> got reports of USB devices plugged in during boot or those plugged in for
> the first time after boot occasionally not working correctly.
> This is partially caused by the USB2 parts of the PHY being left in an
> unknown state by the previous boot stages. We reset all other parts during
> probe but forgot about the USB2 PHY so let's fix that and actually reset
> and power off the USB2 PHY as well.
> 
> Reported-by: James Calligeros <jcalligeros99@gmail.com>
> Reported-by: Janne Grunau <j@jannau.net>
> Fixes: 8e98ca1e74db ("phy: apple: Add Apple Type-C PHY")
> Signed-off-by: Sven Peter <sven@kernel.org>
> ---
>  drivers/phy/apple/atc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/phy/apple/atc.c b/drivers/phy/apple/atc.c
> index c8a58ee64b7aad3205df51cf16ae778471ad2c5d..ab0b40b72533f1b3878b646b59820c730239e85c 100644
> --- a/drivers/phy/apple/atc.c
> +++ b/drivers/phy/apple/atc.c
> @@ -2227,6 +2227,7 @@ static int atcphy_probe_finalize(struct apple_atcphy *atcphy)
>  	_atcphy_dwc3_reset_assert(atcphy);
>  
>  	/* Reset atcphy to clear any state potentially left by the bootloader */
> +	atcphy_usb2_power_off(atcphy);
>  	atcphy_power_off(atcphy);
>  	atcphy_setup_pipehandler(atcphy);

Reviewed-by: Janne Grunau <j@jannau.net>
Tested-by: Janne Grunau <j@jannau.net>

thanks,

Janne